Automatic electric circuit breaker



Oct. 28, 1930. H, PCHEUR AUTOMATIC ELECTRIC CIRCUIT BREAKER Filed June 14 Patented Oct. 28, 1930 VUNITED STATES HENRI PCHEUR, OF STL-OUEN, FRANCE AUTOMATIC ELECTRIC CIRCU 1T BREAKER Application iiled J'une 14, 1927, Serial No. 198,748, and in France April 4, 1927.

The object of my invention is to provide an improved construction of automatic electric circuit breaker' -designed to operate in case of excess of intensity or overload.

5 The chief circuit breaking devices hitherto known may be classed in two categories.

1. Fuses where the circuit is broken by the fusion of a conductor under excess intensity.

2. Circuit breakers in which the circuit is opened by separation of the two parts of the circuit normally in contact this separation being obtained by mechanical devices worked by relays. p

The object of the present invention is the construction of a device for automatically breaking the electric circuit with very great suddenness, in case of excess of intensity.

A device in accordance with this invention consists essentially of a chamber closed hermetically by a plug, the gases in the said chamber being such that intensity, their pressure is so increased that it forcibly ejects the plug and breaks the circuit.

In one form of the invention, the chamber is crossed by a fuse wire forming part of the electric circuit, the volatilization of this fuse wire causing an increase in pressure of the gases in the chamber.

The current can be conveyed to this fusewire through thewall of the chamber on the one hand, and through the plug closing this chamber on the other hand by a flexible wire running to the said plug.

In case of excess intensity of the current the fuse wire is volatilized, and the temperature attained roduces a sufficient pressure of gas to forcibly expel the plug and consequently the current intake pole which is in- 40 side the plug.

The plug acts in tbe manner of a projectile which travels at a high rate of speed and which, owing to its feeble inertia starts very rapidly -and with sufficient speed to give the breaking of the circuit the two following characteristics,-

1. The commencement of the break in the circuit follows the production of the excess intensity very closely.

l1n case of excess' 2. The distance separating the two poles' conveying current to the fuse increases very quickly, considering the speed of the projectile-like plug. l

In some cases it may be arranged to delay thc break bv utilizing the fusion of the fuse wire to ignite a combustible medium which takes a certain time to transmit the flame to an explosive charge which will expel the projectile-like plug.

A -device embodying theinvention is shown by Way of example, drawing, in which Figures 1 and 2 are respectively a vertical section and a plan View.

A is a cylindrical steel tank ylined inside with an insulating facing. A partition B fixed to the lid C divides the tank diametrically into two compartments communicating at the lower end. On the lid C there are two insulators D through each of which runs a rod E, connecting the positive and negative terminals with the fuse wires F. Each fuse wire F is located in an explosion chamber G prolonged by a tubular passage H in which a plug I made of insulating material is held by friction, the said plug having the shape of an elongated olive. A conductor rod runs through the axis of this plug. (The fuse wires F, and the fiexible conductor J which connects them together are fixed to the opposite ends respectively of the said rod. The tank A is filled with oil to the level K; deflectors L are provided to limit the splashing of oil against the lid C.

The circuit is closed through the flexible conductor J and the two fuses are mounted in series.

In case of a short circuit, the fusion of tbe fuse wire F causes a rapid ejection of the plug I; an arc remains struck between tbe side of the explosion chamber and tbe conductor passing throughthe plug; at the instant when the plug is blown out the arc is broken when sufficient distance is attained.

The break therefore is made in the liquid very quickly, the time varying in inverse proportion to the speed of the projected plug, and consequently the violence of the fuse;

second.

The improved apparatus described above the said time is about in the accompanying is applied to break circuits with a voltage of 15,000 volts, for example; the presence of the insulating liquid is not always necessary with lower voltages.

I claim:

1. In an automatic electric circuit breaker, a chamber having conducting inner walls eX- tending all around, enclosing a fluid mass and 4constituting a first pole for the intake current, said chamber being formed with an circuit.- V

2. In an automatic electric circuit breaker,

' a chamber having conducting inner walls extending all around, enclosing a fluid mass and constituting a first pole for the intake current, a plug ofvinsulating material hermetically, closing said chamber, a conductor yeX- tending through said plug and constituting the second pole for the intake current, means controlled by the electric current and adapt-- ed to increase the pressure of the iuid mass in said chamber in case of an excess intensity of the current thereby causing the sudden ejection of said plug and the abrupt automatic break of the circuit, a tank containing an insulating liquid forming a bath for the lower portion of said chamber so that upon the ejection of said plug, due to the increase of pressure of the fluid mass in said chamber, the arc which forms between the lower portion of said chamber and said plug necessarily develops in the insulating liquid contained in said tank, an abrupt extinction of the arc thus being insured. l

3; In an automatic electric circuit breaker,

' a chamber provided with conducting inner walls extending all around, enclosing a fluid mass and constituting a first pole for the intake current, said chamber being formed with so that upon the ejection of said plug the arc forming between said constricted portion and said plug necessarily develops in the insulating liquid in said tank which insures its abrupt extinction.

In testimony whereof I affix my signature.

HENRI Paci-mma.

an enlarged portion and a constricted portion, a plug ofinsulating material placed in said constricted portion and hermetically sealing said chamber, a conductorextending through said'plug and constituting the second pole for the intake current, means controlled by the electric current and adapted to increase the pressure of the 'fluidmass in saidchamber in case of van excess intensity of the current, thereby causing the sudden ejection of said plug and the abrupt auto-- n lgtic break of the circuit, and a tank con'- tairiing 'an insulating liquid forming a bat!v for the constricted portion of said chamba. 

